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Bureau of Mines Information Circular/1982 




Noise and Vibration Control 
for Surface Mines 

Program Document 



By Bradley V. Johnson, Richard J. Seibel, 
and David E. Siskind 




UNITED STATES DEPARTMENT OF THE INTERIOR 



r 

Information Circularj 8876 



Noise and Vibration Control 
for Surface Mines 

Program Document 



By Bradley V. Johnson, Richard J. Seibel, 
and David E. Siskind 




UNITED STATES DEPARTMENT OF THE INTERIOR 
James G. Watt, Secretary 

BUREAU OF MINES 
Robert C. Norton, Director 






This publication has been cataloged as follows: 



Johnson, Bradley V 

Noise and vibration control for surface mines: program 
document. 

(Information circular ; 8876) 

Includes bibliographical references. 

Supt. of Docs.: I 28.27:8876. » 

1. Strip mining— Noise control. 2. Blasting— Noise control. 3- Vibra- 
tion. I. Seibel, Richard J. II. Siskind, D. E. III. Title. IV. Series: In- 
formation circular (United States. Bureau of Mines) ; 8876" 

TN295.U4 [TD893.6.M5] 622s [622.31] 82-600499 AACR2 



OS 

2 CONTENTS 

^ Page 

\j Abstract 1 

Introduction 1 

Program goals 2 

Current status 2 

Research approach 4 

In-house research 4 

Contract research 6 

Appendix A. — In-House Bureau research projects 8 

Appendix B. — Contract Bureau research projects 9 



NOISE AND VIBRATION CONTROL FOR SURFACE MINES 

Program Document 
By Bradley V. Johnson, 1 Richard J. Seibel, 2 and David E. Siskind3 



ABSTRACT 



This publication summarizes the in- 
house and contract research and develop- 
ment projects conducted since 1974 by the 



Bureau of Mines for the control of 
noise and vibrations from surface mine 
blasting. 



INTRODUCTION 



Noise, ground vibration, and 
airblast-produced structure vibrations 
are unwelcome side effects of surface 
mining operations. Uncontrolled, these 
effects can result in an irritated public 
and in cracked walls or broken windows. 

The Bureau's study of blast-produced 
ground vibrations dates back to 1930, 
when a study was initiated to determine 
the damage caused by ground vibration. 
Initial conclusions quantified ground 
vibrations and developed some predictive 
techniques for magnitude based on charge 
weight and distance to a structure.'* 
Statistical studies of structural 
response to both ground vibrations and 
airblasts were conducted in the late 
fifties and the sixties; research 
included analyses of data published by 
others and field tests and analysis of 
blasting vibrations at 25 quarries. 



^Manager, Branch of Mine Waste Control, 
Bureau of Mines, Washington, D.C 

^Chief , Branch of Mine Waste Control, Bu- 
reau of Mines, Washington, D.C. 

■^Supervisory geophysicist. Twin Cities 
Research Center, Bureau of Mines, Twin 
Cities, Minn. 

'^Thoenen, J. R. , and S. L. Windes. Seis- 
mic Effects of Quarry Blasting. Bu- 
Mines Bull. 442, 1942, 83 pp. 



Areas of investigation consisted of 
seismic instrumentation, safe vibration 
levels for residential structures, gener- 
ation and propagation of ground vibra- 
tions and airblasts, and prediction of 
ground vibration and airblast levels. 
For quarry blasting, relatively small 
blasthole diameters and charge weights 
are used. However, in surface coal 
mines, over a ton of explosives can be 
loaded into a hole over a foot in diam- 
eter. Coal mine blasts are often 
designed to fracture the rock in place 
rather than throwing it onto the pit 
floor. This can reduce airblast but at 
the risk of increased ground vibration. 
To make reasonable recommendations for 
surface coal mining, a new set of vibra- 
tion data was needed. The Bureau began 
this study of surface coal mine blasting 
in 1974. Currently over 15,000 blast 
records are being analyzed and new recom- 
mendations are being formulated. 

In 1978, the Bureau began a study of 
noise produced from sources other than 
blasting. This work initially gathered 
information on general noise abatement 
techniques and then listed major noise 
sources. Large haulage trucks have been 
found to be a major source of noise both 
in the mining pit and on public roads. 
Research is now being focused on con- 
trolling this noise. 



PROGRAM GOALS 



The goals of the Bureau's noise and 
vibration control program are to develop 
and demonstrate (1) proper mine blasting 
practices and (2) proper ground vibration 
and noise controls for surface mining 
operations. To accomplish these goals, 
the following objectives have been 
established: 



1. To control blast noise 
contour mining in Appalachia. 



from 



2. To determine the fatigue effect 
of repeated surface mine blasting on res- 
idential structures. 

3. To develop blast designs that 
minimize airblast and ground vibration 
and to develop a handbook of blast 
design, all consistent with good blasting 
principles and fragmentation. 



environmental impact and improve 
fragmentation. 

5. To determine propagation and 
frequency characteristics in low-velocity 
geolgic media. 

6. To develop a simple weather 
assessment technique and criteria for 
adverse weather applicable to mines with 
potential airblast problems. 

7. To develop remote monitoring 
methods. 

8. To improve flyrock control. 

9. To improve stemming techniques. 

10. To identify, categorize, and 
rank surface mine noise sources. 



4. To apply precision blast ini- 
tiation devices to control adverse 



11. To develop noise 
large haulage trucks. 



controls for 



CURRENT STATUS 



Adverse environmental effects from 
surface mining activities continue to be 
a major problem for the mining industry, 
the public living near mining operations, 
and the governmental agencies responsible 
for setting environmental standards. 
Congress, in recognizing this problem, 
passed the Surface Mining Control and 
Reclamation Act of 1977, which addresses 
many specific environmental effects, 
including the noise and vibrations from 
blasting and other mining operations. 

Blasting in the mining, quarrying, 
and construction industries used 4 bil- 
lion pounds of explosives in 1980. The 
necessity of blasting for most mineral 
production, or wherever rock must be 
excavated, has led to two sets of techni- 
cal problems: environmental effects and 
design variables influencing fragmenta- 
tion. Large surface coal mines have 
had to close because of widespread 



complaints. Other mines have had to 
abandon many tons of previously purchased 
coal rights because of blasting vibration 
or have been required to agree to exces- 
sively strict vibration levels for their 
operating permits. 

The regulatory agencies have been 
asked to close down "irresponsible 
blasters." Public interest groups have 
claimed widespread damage from airblasts, 
ground vibrations, and flyrock. Con- 
flicts abound at the State and local 
level concerning environmental regulation 
of these effects, permit granting, hear- 
ings, and lawsuits. Even prior to the 
1977 Surface Mining Act, 17 States had 
regulations on blasting vibrations based 
on Bureau research, and in 1974 blast 
noise standards were proposed in Illinois 
that threatened to halt all blasting in 
the State. 



The Bureau completed four major 
studies of blast effects from coal and 
other types of surface mining in 1980.^ 
These studies identified the major fac- 
tors in the design of production blasts 
that influence airblast and ground vibra- 
tion levels. They also determined levels 
of ground vibration and airblast that 
correspond to acceptable structure 
response and damage potentials, and made 
a comprehensive analysis of measurement 
systems. Results were needed by the min- 
ing industry and the regulatory agencies 
for realistic, technically based, and 
defensible criteria for allowable blast- 
induced ground vibrations and airblasts. 

The Bureau's research program 
emphasizes improved minerals production 
and the establishment of essential and 
realistic environmental, health, and 
safety guidelines. For blasting in par- 
ticular, there have been efforts to 
determine safe-level criteria for ground 
vibration and airblast. These criteria 
should provide the basis for realistic, 
technologically established, and defen- 
sible regulatory levels, and also for 
practical blast design for the industries 
that use explosives. 

The work on noise control is not as 
advanced. An annotated bibliography on 
noise abatement techniques has been 

^Siskind, D. E. , V. J. Stachura, 
M. S. Stagg, and J. W. Kopp. Struc- 
ture Response and Damage Produced by 
Airblast From Surface Mining. BuMines 
RI 8485, 1980, 111 pp. 

Siskind, D. E., M. S. Stagg, J. W. Kopp, 
and C. H. Dowding. Structure Response 
and Damage Produced by Ground Vibra- 
tion From Surface Mine Blasting. Bu- 
Mines RI 8507, 1980, 74 pp. 

Stachura, V. J., D. E. Siskind, and 
A. J. Engler. Airblast Instrumenta- 
tion and Measurement Techniques for 
Surface Mining. BuMines RI 8508, 
1981, 53 pp. 

Stagg, M. S., and A. J. Engler. Mea- 
surement of Blast-Induced Ground 
Vibrations and Seismograph Calibra- 
tion. BuMines RI 8506, 1980, 62 pp. 



established. Under existing contract 
JOlOOOOl, "Technology for Environmental 
Noise Control in Surface Mines," the 
Bureau is investigating the sources and 
relative levels of noise from surface 
mines. One of the sources identified has 
been the large haulage trucks used in the 
surface mines. Because they are built 
for off-highway use they are not designed 
to meet EPA noise criteria. Most of the 
techniques used to protect the workers 
have taken the form of special cabs 
which, while they protect the driver from 
excessive noise, do not reduce the noise 
radiated to the surrounding areas . A 
follow-on contract will use recommenda- 
tions from contract JOlOOOOl to develop 
techniques for reducing the noise from 
large haulage trucks. Prototype tech- 
niques will be applied to trucks and 
demonstrated under actual operating 
conditions. 

Comprehensive blast design work is 
continuing. One important parameter, 
delay timing, is now being researched 
with the goal of developing a precise 
blast initiation system to insure proper 
blast delay intervals. A system is now 
undergoing laboratory development, with 
field tests scheduled for 1983. 

The fatigue effect of repeated 
blasts is not known. The Bureau of Mines 
has built a full-scale test structure to 
study this and other effects, such as 
settlement, at the Ayshire Mine near 
Evansville, Ind. Field data are now 
being gathered, and analysis will begin 
soon. 

Future work will also include a 
study of the effects of blasting on 
hydrology and fugitive dust generation. 
Another aspect is the human response to 
blast noise and vibrations. 

Determination of safe technical 
criteria is only one factor in the 
establishment of environmental control. 
To insure that recommended controls are 
practical for the mining industry, the 
social, legal and economic effects of a 
control must also be considered. 



The end results of the program will 
be a conprehensive set of operating 
paraneters that, when followed, will help 
guard against environmental damage while 



enabling mines to supply the country with 
the necessary minerals in an economical 
manner. 



RESEARCH APPROACH 



The Bureau of Mines is in continual 
contact with the raining industry and 
other Federal agencies. The Bureau 
learns of current mining problems through 
interactions at mining symposia and 
through visiting and working in mining 
operations. The industry makes numerous 
requests for Bureau information and 
receives additional data through Bureau 
publications and presentations. The 
Bureau also has a close working relation- 
ship with both State and Federal agencies 
that have programs relevant to the 
Bureau ' s concerns . 

It is through these continual inter- 
actions that the Bureau identifies mining 
problems and their priorities; such 
interactions are also essential for tech- 
nology transfer. Formal vehicles for 
technology transfer include presentations 
at mining symposia. Bureau publications, 
open industry briefings, technology 
transfer seminars, journal articles, 
technology demonstrations, films, and 
exhibits at professional and industrial 
meetings. 



The 

involves — 



process cycle 



typically 



2. Problem identification. 

3. Problem prioritization and Gov- 
ernment interaction. 

4. Research. 

5. Problem solution. 

6. Evaluation and feedback, 

7. Technology transfer through 
industry interaction, briefings, presen- 
tations, and publications. 

This cycle is made possible 
through expertise gained under a 
strong in-house research program. If 
personnel is limited, portions of set 4 
in the cycle are contracted out. The 
result is an integrated program that 
is responsive to the needs of the mining 
industry and of the Nation, 

Technology transfer seminars on 
Ground Vibrations and Airblast Control 
were presented on November 5, 1980, in 
Chicago, 111,; on December 3, 1980, in 
Denver, Colo,; and on December 17, 1980, 
in Washington, D,C, 



1. Industry interaction. 



IN-HOUSE RESEARCH^ 



Assessment of Damage from Blast-Induced 
Ground Vibrations 

This project determined the thresh- 
olds of damage for cyclic repetitions of 
low vibration levels as well as for sin- 
gle exposures to high levels of vibra- 
tion. Existing or new structures were 
subjected to blast-induced vibrations at 
levels that actually produced observable 
damage. Also small structures were 

"Dates and funding appear in appendix A. 



subjected to many repetitions of simu- 
lated blast vibrations on large-scale 
shaking tables, with the results corre- 
lated to previous studies and field tests 
on similar structures, 

Airblast Assessment and Control 

The project determined the important 
variables for controlling the generation 
and propagation of noise from blasting, 
developed techniques for minimizing noise 
levels, and established noise and damage 



thresholds for use in developing regula- 
tions. The initial task was a survey of 
the literature to determine the important 
variables for controlling airblast. 
Field tests were designed, using this 
information, to evaluate the instrumenta- 
tion available for impulsive noise level 
measurement, to determine the effects of 
generation and propagation variables on 
noise levels, and to establish safe noise 
level criteria. 

Evaluation of Current Methodologies 
for Ground Vibration Measurement 

Increased interest by all sections 
of industry and Government in ground 
vibration problems necessitated a stan- 
dardized methodology for determining 
ground vibration levels. The Bureau of 
Mines, in an unbiased capacity, evaluated 
existing instrumentation, methods, and 
measurement criteria to produce a reason- 
able standardized measurement system. 
This will permit efficient planning for 
new mine monitoring systems and help 
insure compliance with environmental 
statutes. 

Collection and Analysis of Ground 

Vibration Data From Surface 

Mine Blasting 

This project determined ground 
vibration levels for surface coal mine 
blasting that will permit economical min- 
ing yet will minimize damage from blast- 
ing. Experimental work measuring vibra- 
tions from actual mine blasts was 
combined with previous blast vibration 
work to achieve guidelines that will 
include effects of structural fatigue 
damage as well as damage from single 
shots. 

Evaluation of Noise-Measuring Devices 
for Airblast Transients 

This project examined techniques for 
the measurement of blast noise overpres- 
sures and evaluated the performance of 
commercially available impulse precision 
sound level meters and carrier-type sys- 
tems designed for sonic boom studies. 
Using recorded blast signals, measurement 



methods such as peak, root mean square, 
linear or flat, and C-weighted were 
investigated. Recommendations were made 
on instrumentation and measurement tech- 
niques for airblast noise measurement at 
surface mines. 

Determination of Criteria for Ground 

Vibration Damage From Surface 

Mine Blasting 

Damage caused by ground vibrations 
from surface coal mine blasting is a 
serious problem for both mine operators 
and governmental agencies responsible for 
regulating these adverse environmental 
effects. Appropriate permissible levels 
for blast-produced ground vibrations will 
be determined, permitting economical min- 
ing while minimizing damage to nearby 
residences. Field measurements from coal 
mine blasts will be combined with previ- 
ous blast vibration work and response 
spectra analysis techniques to develop 
safe levels that will include effects of 
repeated blasting damage as well as 
damage from single shots. 

Control of Blast Noise and Vibration 
From Contour Mining of Coal 
in Appalachia 

Airblast and ground vibration 
effects on structures from the contour 
mining of coal in Appalachia will be 
determined. Many complaints on record 
for the Appalachian Coal Region indicate 
that the particular topography and mining 
method may generate abnormal levels of 
airblast and ground vibrations. The 
applicability of blasting criteria devel- 
oped for midwestern surface coal mining 
will be evaluated, and if required, 
specialized criteria will be developed 
for Appalachian mining. 

Fatigue and Structural Damage 

From Repeated Surface 

Mine Blasting 

Fatigue damage to structures from 
repeated blasting is an often-posed prob- 
lem to the mining industry and the gov- 
ernmental agencies responsible for reg- 
ulating these adverse environmental 



effects. Appropriate criteria will 
be recommended, incorporating the 
results of this long-terra single- 
structure with data from concurrent 
fatigue model tests and the peak-level 
criteria developed from previous short- 
term studies. 

Application of Abatement Technique 
to Mine Environmental Noise Problems 

The objective of this project 
was to determine and promote the 
application of noise abatement techniques 
to the solution of fugitive mine 
noise problems. Noise emissions were 
identified, characterized, and quanti- 
fied, and cost-effective abatement 
technology was described. Changes 
necessary in mining systems to provide 
isolation of noise sources, were 
identified. 

Blast Design To Minimize Airblast 
and Ground Vibration 

The objective of this project 
is to develop blast design cri- 
teria to minimize airblast and ground 
vibrations and still permit effective 
blasting programs at surface mines. Past 
work will be integrated with new 
data on delay intervals and use 
of decking. Other blast design param- 
eters will also be considered for 
research as needed. 



Analysis and Technical Clarification 
of Ground Vibration and 
Airblast Standards 



In developing criteria for control 
of damage and annoyance levels of air- 
blast and ground vibration and associated 
measurement methods (descriptors), both 
the National Academy of Science-sponsored 
Committee on Hearing and Bioacoustics 
(CHABA) and the Army Corps of Engineers 
have supplied support to the Interna- 
tional Standards Organization, American 
National Standards Institute, the U.S. 
Department of Housing and Urban Develop- 
ment, and U.S. Environmental Protection 
Agency. Their recommendations will be 
analyzed and critiqued for applicability 
to blasting. This will involve partici- 
pation in working group meetings, an 
effort that has already been initiated. 
Although none of the criteria proposed so 
far include any blasting data, they are 
often more stringent than the Bureau's 
well-founded recommendations for airblast 
and ground vibration. 

Feasibility of the Development 
of a Precious Blast 
Initiation System 

Current delay blasting systems will 
be studied, and alternatives to pyro- 
technic delay caps analyzed. Experi- 
mental prototypes will be built and 
tested in the laboratory, and a feasibil- 
ity and cost analysis will be done. 



CONTRACT research"^ 



Control of Vibration and Blast Noise 
From Surface Coal Mining (JO255022) 



2 years work, 
completed. 



The contract has been 



(Wiss, Janney, Elstner 
and Associates, Inc.) 

The objective of this work was to 
determine the extent of adverse environ- 
mental effects of airblast and ground 
vibrations from surface coal mine blast- 
ing and to develop blasting techniques to 
minimize these effects. The project was 
divided into three phases covering 

'Dates and funding appear in appendix B. 



Survey of Blast Damage to Water Supplies 
in Appalachla (JO285029) 

(Philip R. Berger and Associates) 

The objective of this contract was 
to determine possible adverse environ- 
mental effects of blasting on ground 
water supplies in close proximity to con- 
tour coal mining operations in 
Appalachla. Ground vibrations associated 
with surface coal mine blasting are a 



major problem to homeowners near the mine 
sites. Not only can the vibrations cause 
damage to the residences, as shown in a 
number of Bureau studies, but a number of 
complaints exist in contour strip mining 
areas concerning loss of, or damage to, 
water wells caused by blasting. The 
final report will be available in 1982. 

Human Response to Blast Noise and Ground 
Structure Vibrations (JO206009) 

(Bolt, Beranek and Newman) 

This study will determine, by field 
surveys and field tests, levels of 
surface-mine-blasting-induced ground vi- 
brations and airblast that are per- 



ceptible, 
humans. 



annoying , 



or intolerable to 



coordinating responsibility, specifically 
in the technical areas of human and 
structural tolerance and measurement of 
noise and vibration. 

Technology for Environmental Noise 
Control in Surface Mines (JOlOOOOl) 

(ORI, Inc.) 

Work under this contract will 
identify the environmental noise problems 
associated with mining operations, 
develop techniques for monitoring such 
noise, and identify and recommend tech- 
nology for abatement of noise problems. 

Technology for Control of Environmental 

Noise From Off Road Haul Trucks 

(J0218020) 



Standards on the Measurement of Human 
Acceptability of Blast Noise and 
Ground-Transmitted Vibration and 
Shock (JO205020) 

(Acoustical Society of America) 

This contract provides for adminis- 
tration of the national and international 
standards committees for which the 
Acoustical Society of America holds 



(Woodward Associates) 

This contract supports the develop- 
ment of cost-effective techniques for 
reducing the sound radiated from large 
haulage trucks without significantly 
reducing the efficiency of the trucks. 
Prototype techniques will be applied to 
trucks and demonstrated under actual 
operating conditions. 



APPENDIX A.— IN-HOUSE BUREAU RESEARCH PROJECTS 

Research Area: Minerals Environmental Technology 

Research Program: Noise and Vibration Control From Surface Mine Blasting 

Research Center: Twin Cities 





Starting date 


Expected 
completion 


Funding, thousand dollars 


Project 


FY 
75 


fy1 

76 


FY 
77 


FY 
78 


FY 
79 


FY 
80 


FY 
81 


FY 
82 


Assessment of Damage From 
Blast-Induced Ground 
Vibrations. 


FY 75—7/1/74 


Completed 


60 


175 














Airblast Assessment and 
Control. 


FY 75—7/1/74 


Completed 


100 


125 


120 


130 


- 


- 


- 


- 


Evaluation of Current Method- 
ologies for Ground Vibration 
Measurement. 


FY 77—10/1/76 


Completed 


— 


— 


35 


~ 


~ 


~ 


~ 


~ 


Collection and Analysis of 
Ground Vibration Data From 
Surface Mine Blasting. 


FY 77—10/1/76 


Completed 


~~ 




175 


— 


"~ 


~" 




^ 


Evaluation of Noise-Measuring 
Devices for Airblast 
Transients. 


FY 77-10/1/76 


Completed 


— 


— 


35 


_ 


~ 


~ 




— 


Determination of Criteria for 
Ground Vibration Damage From 
Surface Mine Blasting. 


FY 78—10/1/77 


Completed 


— 




~ 


100 


~ 


~ 


~ 


— 


Control of Blast Noise and 
Vibration From Contour Min- 
ing of Coal in Appalachia. 


FY 78—10/1/77 


Completed 


~ 




" 


■ 


120 


90 


130 


' 


Fatigue and Structural Damage 
From Repeated Surface Mine 
Blasting. 


FY 79—10/1/78 


9/30/84 


— 


— 


— 


100 


100 


75 


70 


160 


Application of Abatement 
Techniques to Mine Environ- 
mental Noise Problems. 


FY 79—10/1/78 


9/30/83 


_ 


— 


~ 


~ 


20 


30 


65 


~ 


Blast Design To Minimize Air- 
blast and Ground Vibration. 


FY 79—10/1/78 


9/30/85 






- 


- 


50 


90 


120 


130 


Analysis and Technical 
Clarification of Ground 
Vibration and Airblast 
Standards. 


FY 80—10/1/79 


9/30/83 












20 


20 


50 


Feasibility of the Develop- 
ment of a Precise Blast 
Initiation System. 


FY 81 — 10/1/80 


9/30/87 


- 


- 


- 


- 


- 


- 


50 


100 


Total 


160 


300 


365 


330 


290 


305 


455 


440 



^Includes transition quarter. 



APPENDIX B. - CONTRACT BUREAU RESEARCH PROJECTS 



Research Area: 
Research Program: 



Minerals Environmental Technology 

Noise and Vibration Control From Surface Mine Blasting 





Starting 
date 


Expected 
completion 


Funding, thousand dollars 


Project 


FY 
75 


FY1 
76 


FY 
77 


FY 
78 


FY 
79 


FY 
80 


FY 
81 


FY 
82 


JO255022— Control of Vibration 
and Blast Noise From Surface 
Coal Mining. 


1975 


Completed 


535 








2 








JO285029— Survey of Blast Dam- 
age to Water Supplies in 
Appalachia. 


1978 


1982 


•~ 


"~ 


~~ 


267 


— 


31 


— 


— 


JO206009 — Human Response to 
Blast Noise and Ground Struc- 
ture Vibrations. 


1980 


1982 


^ 


— 


— 


■" 


— 


202 


121 


^ 


JO205020~Standards on the 
Measurement of Human Accepta- 
bility of Blast Noise and 
Ground Transmitted Vibration 
and shock. 


1980 


1982 












10 


10 




J0100001~Technology for En- 
vironmental Noise Control in 
Surface Mines. 


1980 


Completed 


— 


— 


— 


— 


— 


76 


— 


— 


J0218020~Technology for Con- 
trol of Environmental Noise 
From Off Road Haul Trucks. 


1981 


1983 


- 


- 


- 


- 


- 


103 


- 


- 


Total 


- 


- 


535 


- 


- 


267 


2 


422 


131 


- 



^Includes transition quarter. 



INT.-BU.OF MINES,PGH.,P A. 26005 



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